A cross-flow fan for use in conventional air conditioners includes a cross-flow impeller having a plurality of fan bodies linked together, and a rear guider and a stabilizer, which are arranged across the impeller for guiding fluid from an inlet toward an outlet. The rear guider is arranged to have an area covering the side peripheral surface of the impeller larger than that of the stabilizer, and the stabilizer is arranged at a position nearer to the side peripheral surface of the impeller than the rear guider. The rear guider is provided with concave portions formed continuously in a direction perpendicular to the fluid flowing direction, thereby reducing an interference sound produced at a gap between the impeller and the rear guider (see Patent Document 1, for example). The concave portions are formed slightly obliquely to the direction perpendicular to the fluid flowing direction.
There is an air conditioner in that the stabilizer with a lingual surface arranged close to the fan is provided with a plurality of projections formed on the lingual surface, each being inclined at a predetermined angle to each of the plurality of vanes of the fan (see Patent Document 2, for example).
There is also a transverse flow blower in that the stabilizer is provided with a plurality of projections formed on an arc-shaped part adjacent to the fan so as to increase and stabilize the eddy current force generated at the arc-shaped part of the stabilizer for improving the blowing performance (see Patent Document 3, for example).
[Patent Document 1]    Japanese Unexamined Patent Application Publication No. 2000-205180 (P03, FIG. 9)
[Patent Document 2]    Japanese Unexamined Patent Application Publication No. 9-170770 (P03, FIG. 2)
[Patent Document 3]    Japanese Unexamined Patent Application Publication No. 11-22997 (P02, FIG. 1)